Why is the equation incorrect? Mg₃ + N₂ → Mg₃N₂
(A) Some of the subscripts are incorrectly used.
(B) The equation is not balanced.
(C) The valence of the nitride ion is incorrect.
(D) The valance of the magnesium ion is incorrect.
(E) The coefficient of N₂ is incorrect.
Can someone explain this one?